In a statement issued later, he added: "It is a huge privilege to join the Cabinet as Secretary of State for Wales. As a government, we are ambitious for Wales and determined that Wales should be at the forefront of the UK economic recovery.

"I will be working closely with my colleagues in the UK and Welsh governments to see new opportunities created for Wales. People and businesses across Wales want to see the two governments working together effectively and delivering the investment our nation needs. I believe that Wales deserves the best and I look forward to providing a strong voice for Wales around the Cabinet table.

"I will build on the excellent work of my predecessor, David Jones, who achieved so much during his time as Welsh Secretary. He leaves a strong legacy to Wales, not least in breaking new ground in the devolution settlement by devolving tax powers to Wales.

"He also worked hard to secure new investment for the new nuclear power station at Wylfa, the new prison in Wrexham and reopening the Halton Curve line between Liverpool and North Wales.

"It is a massive honour to be the first Welsh Secretary of State from Pembrokeshire since Nick Edwards in the 1980s. I have an opportunity now to work hard for the whole of Wales in the same way I have always sought to do for Pembrokeshire.

"The first priority of any MP, regardless of their position in government, is to put the needs of their constituency first and I will always do this for Preseli Pembrokeshire."

Alun Cairns has been appointed as a junior minister in the Wales Office.

Alun Cairns has been appointed as Parliamentary Under Secretary of State @walesoffice and Government Whip #reshuffle

Clwyd West MP Mr Jones was sacked by Prime Minister David Cameron on Monday as part of a cabinet reshuffle.

Mr Jones said he was not unhappy, adding: "The prime minister has my total support."

Shadow Welsh Secretary Owen Smith said: “Congratulations to Stephen Crabb on his appointment as the third Secretary of State for Wales in the last 22 months. It is a great privilege for anyone to be asked to serve as the Secretary of State for our country and Mr Crabb now has an equally great responsibility to break free from the ceaseless negativity that has characterised his predecessors’ attitude to Wales and the achievements of the Welsh Government.

“I have written to the new Secretary of State today to formally offer my congratulations, but also to call on him to go into the new job with the aim of standing up for our nation, rather than indulging in politicised attacks on Wales, with the aim of winning votes in England.

“The Wales Office can play a vital role in being the voice of Wales at Westminster, but it has recently been reduced to a crude propaganda machine attacking the very country it is supposed to represent, as a proxy for attacking the wider Labour Party. Speaking from the steps of 10 Downing Street Mr Crabb has this morning pledged to ‘work hard for Wales’.

“I hope and trust that will be the case, and that the war on Wales might end on his watch.”

Referring to a 2007 article for the website Conservative Home, Mr Smith said: “Mr Crabb shares with his predecessor a long stated scepticism about the value of devolution, calling it in the past a form of ‘constitutional vandalism’, and he will thus face legitimate questions about his commitment to the devolved settlement and his desire to take it forward. “He not long ago lamented that it was no longer saleable ‘to call for the abolition of the devolved institutions’. Let’s hope he takes a more enlightened view now he’s responsible for them. A key test for Mr Crabb in this regard will be whether he supports the Silk Commission and Labour’s view that our country should have the same, ‘reserved’ model of devolved powers as those applied in Scotland.”

Andrew RT Davies, Conservative Leader of the Opposition in the National Assembly, said: “I congratulate my close colleague Stephen Crabb on his promotion and very much look forward to working with him. Stephen Crabb has been an effective and hardworking Minister and will be a powerful advocate for Wales around the cabinet table.

“I am grateful to David Jones who oversaw radical legislation to make the Welsh Government accountable for raising a proportion of the money it spends and worked tirelessly to promote Wales as a place for business and enterprise. This reshuffle has delivered a modern and dynamic team to offer voters a clear choice between the Conservatives’ long term economic plan for Britain or more borrowing, spending and debt under Ed Miliband.”

Janet Jones of the Federation of Small Businesses said: “We congratulate Stephen Crabb as the new Secretary of State for Wales and we look forward to working with him on behalf of our members in communities across Wales. We would like to put on record our thanks to his predecessor David Jones who has been a good friend to the small business community and who placed a welcome focus on the economy of Wales.

“Perhaps his greatest legacy will be that he has set in track the full devolution of business rates to Wales, something that will from next April give the Welsh Government a vital economic lever to aid smaller businesses.”

CBI Wales Director Emma Watkins said: “David Jones worked diligently to promote Wales as a place to do business and we look forward to building on those successes with Stephen Crabb. At the top of the business agenda should be improving Wales’ global competitiveness and focussing efforts to tackle the cost of energy facing our manufacturing base and secure and delivery the infrastructure needed for growth.”

The biggest surprise of the reshuffle was Michael Gove being moved from his Education brief.

The pugnacious former journalist is to become "minister for TV" with a brief to promote the Government's message in broadcast interviews as he shapes up to fight for a Conservative majority in next year's general election.

In the most dramatic reshuffle of his premiership, Mr Cameron also promoted Defence Secretary Philip Hammond to replace William Hague as Foreign Secretary after the surprise announcement last night that the former Tory leader was moving to become Leader of the Commons before quitting as an MP next year.

Treasury minister Nicky Morgan, 41, who replaces Mr Gove as Education Secretary, is expected to be one of a number of women and younger MPs being promoted by Mr Cameron in an attempt to counter perceptions that his Cabinet is too "male, pale and stale".

Liz Truss becomes the youngest member of Cabinet at 38 after being appointed Environment Secretary to replace Owen Paterson, who ran into trouble over the failed badger cull and his handling of the winter floods, as well as antagonising green groups with his scepticism about man-made climate change.

Mr Gove's move to Chief Whip will be seen in Westminster as a demotion from a job in which he has shown a personal passion for free schools and stringent academic standards but has met fierce opposition from teaching unions.

Mr Gove's removal was welcomed by teaching unions - part of the educational establishment which he reportedly derided in private as "the blob".

General secretary of the Association of Teachers & Lecturers (ATL) Mary Bousted said: "David Cameron has belatedly realised that Michael Gove's ideological drive is no substitute for measured, pragmatic reform of the education system.Time after time he has chased newspaper headlines rather than engage with teachers.

"The dismantling of the structures which support schools, the antagonism which he displayed to the teaching profession and the increasing evidence of chaos in the bodies he established, in particular the Education Funding Agency, has led Cameron to one conclusion - Gove is more of a liability than an asset.

"Successful education systems value the views of the teaching profession, which Gove insulted when he called them 'the blob'. ATL looks forward to a more constructive relationship with his successor, Nicky Morgan."

Labour described the reshuffle as a "massacre of the moderates" which marked a shift to the right by Mr Cameron less than a year ahead of the 2015 general election.

Among casualties of the reshuffle were David Jones, who was removed as Welsh Secretary and is expected to be replaced by his deputy Stephen Crabb, while Mr Cameron is expected to confirm that Environment Secretary Owen Paterson - whose allies mounted a desperate rearguard effort to save him - and Attorney General Dominic Grieve have been sacked.

Downing Street said the Prime Minister also accepted the resignations of universities minister David Willetts and energy and climate change minister Greg Barker, who will both stand down as MPs next year.

Andrew Robathan quit as a minister in the Northern Ireland Office and Alan Duncan left his post at international development, while news of Hugh Robertson's resignation from the Foreign Office filtered through while he was on an overseas trip in Beirut.

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